The Internet and its associated worldwide web (WWW) are well-known and established communication networks. Increasingly, business applications are employing the worldwide web to transfer print jobs from client processors to network printers that are remotely located. A significant feature of the worldwide web is that it offers a common interface which enables computing devices that are controlled by different operating system platforms to communicate and to be understood by each other. This communication capability arises as a result of each of the operating system platforms having program modules which enable the devices to communicate via the common messaging protocol used over the worldwide web.
That protocol is termed the "HyperText Transfer Protocol" or HTTP. HTTP provides a way for WWW clients and servers to communicate, primarily through the exchange of messages that are brief and direct. HTTP employs specific message categories, i.e.: a "connection"; a "request"; a "response" and a "close". A connection is a message which occurs as a client tries to connect to a specific web server. As will be understood from the description below, a network printer which incorporates the invention operates as a web server and is accessed by client processors.
A request is when a client processor asks for a web resource it is looking for. Such request includes the protocol to be used, the name of the object being sought (i.e. its universal resource locator or URL), and information about how the server should respond to the client processor.
A response is a server's message which responds in the manner requested by the client processor and delivers the requested data. A close occurs after the information has been transferred in response to the request. The connection can then be re-opened with another request, for example, by clicking on a link in a current web page.
An Internet printing system, recently announced by the Pipeline Corporation (see "The Hard-Copy Observer", pages 45, 46, March 1997), describes a network printer that includes functions which enable a URL of a print job to be received. The printer's home page includes a field that allows a user to enter URLs of desired pages to be printed. The printer includes scheduling software which allows a user to program the printer to periodically access a prescribed list of web sites and to automatically print the pages it finds there. The system also enables the printer to be programmed to retrieve and print pages that are hyperlinked to an original document, down a specified number of link levels.
Because many client processors can access network printers over the worldwide web, such a printer must have an ability to establish a queue for received print jobs so as to enable such print jobs to be handled in an orderly manner. It is desirable, however, that client processors have an ability to view the printer's print queue and, to access information regarding the status of each print job on the print queue. Further it is desirable that a client processor have an ability, if authorized, to alter the print queue. Such a capability will enable the print queue to be a "universal queue" that is accessible by any number of client processors and will enable each client processor to render an informed decision regarding whether it wishes to use the particular network printer. Also, the capability will provide an ability to remotely modify the print queue, in accordance with preassigned priority client queue management rights.
Accordingly, it is an object of this invention to provide a network printer with a capability to establish a universal print queue.
It is another object of this invention to provide a network printer with an ability to report print queue status data to client processors.
It is yet another object of this invention to provide a network printer with an ability to respond to HTTP-configured messages and to both report print queue status and to retrieve print jobs in response thereto.
It is yet another object of this invention to enable a scanner device attached to the WWW to provide a URL indicator to a printer and for the printer to respond by accessing a scanned image.